Genotypic and morphological variation between Galaxiella nigrostriata (Galaxiidae) populations: implications for conservation

2015 ◽  
Vol 66 (2) ◽  
pp. 187 ◽  
Author(s):  
David M. Galeotti ◽  
Mark A. Castalanelli ◽  
David M. Groth ◽  
Clint McCullough ◽  
Mark Lund
Keyword(s):  
Morphological Variation ◽  
Coastal Plain ◽  
Coastal Wetlands ◽  
Morphological Differentiation ◽  
Early Pleistocene ◽  
Genetic Connectivity ◽  
Small Fish ◽  
Seasonally Dry ◽  
Swan Coastal Plain ◽  
South West

Galaxiella nigrostriata is a freshwater fish that is endemic to the seasonally dry coastal wetlands of south-west Western Australia and considered by the International Union for Conservation of Nature (IUCN) as lower risk–near threatened. This small fish (maximum total length<50mm) aestivates in the sediment over the long, dry Mediterranean summer and its dispersal is limited by lack of habitat connectivity. The objective of this study was to identify the historical and contemporary genetic connectivity between populations of G. nigrostriata and to assess morphological variation between these populations. Results showed that all populations were genetically divergent and no mtDNA haplotypes were shared between populations. In contrast, morphological differentiation between individual populations was weak; however, pooling populations into two broad regions (Swan coastal plain and southern coast) resulted in clear morphological differentiation between these two groups. Based on these results, we postulate G. nigrostriata distribution last expanded in the early Pleistocene ~5.1 million years ago and have since been restricted to remnant wetlands in the immediate area. Galaxiella nigrostriata populations at the northern end of their range are small and are the most vulnerable to extinction. Conservation efforts are therefore required to ensure the survival of these genetically and morphologically distinctive Swan coastal plain populations.

Genetic and morphological analysis of multi-stemmed plants of tuart (Eucalyptus gomphocephala)

2016 ◽  
Vol 64 (8) ◽  
pp. 704 ◽  
Author(s):  
M. Byrne ◽  
A. Koenders ◽  
K. Rogerson ◽  
J. Sampson ◽  
E. J. B. van Etten
Keyword(s):  
Coastal Plain ◽  
Morphological Analysis ◽  
Growth Form ◽  
Growth Habit ◽  
Coastal Region ◽  
Morphological Differentiation ◽  
Genetic Influences ◽  
Swan Coastal Plain ◽  
Eucalyptus Gomphocephala ◽  
Stressful Environments

The tuart–banksia woodlands of the Swan Coastal Plain in Western Australia are characteristic vegetation communities of this coastal region, and Eucalyptus gomphocephala DC. (Myrtaceae; tuart) is an iconic tree of these communities. The species primarily occurs as a tall single-stemmed tree, but at the northern end of the distribution, it also occurs in a multi-stemmed form. Growth habit is frequently used as a taxonomic character in eucalypts, with many complexes having tree and mallee forms, although the genetic characterisation of growth habit in eucalypts has been limited. We investigated the genetic and morphological differentiation among populations of tree and multi-stemmed forms of tuart at the northern end of its distribution. Although the populations showed moderate levels of genetic diversity on the basis of microsatellite markers, as might be expected from populations on the periphery of the distribution, there was no evidence of genetic differentiation associated with the tree and multi-stemmed forms. Morphometric analysis showed some differences in the size of buds and fruits among the populations. Our analysis is consistent with environmentally induced variation in tuart in near-coastal populations where plants grow on poor soils and form may be affected by wind and salt exposure. This result adds to other evidence from pines and Nothofagus of environmental rather than genetic influences on growth form, particularly in stressful environments.

Radiological consequences of amending soils with bauxite residue gypsum mixtures

Soil Research ◽  
1993 ◽  
Vol 31 (4) ◽  
pp. 533 ◽  
Author(s):  
KJ Summers ◽  
BH O'Connor ◽  
DR Fox
Keyword(s):  
Coastal Plain ◽  
Soil Amendment ◽  
Radiation Flux ◽  
Bauxite Residue ◽  
Sandy Soils ◽  
Linear Increase ◽  
Swan Coastal Plain ◽  
South West ◽  
Application Rates ◽  
Incremental Dose

This paper reports on the gamma (�) radiation flux from sandy soils of the Swan Coastal Plain treated with bauxite residue/gypsum at various application rates and assesses the radiological significance of soil amendment in relation to currently accepted standards. Amendment rates of up to 2000 t ha-1 of bauxite residue were used. There is a linear increase of incremental � dose with increasing rate of residue. The 1 mSv limit for incremental � dose exposure for the general public is reached for 100% occupancy at an amendment rate of 1500 t ha-1 of bauxite residue. The gamma rate of approximately 0.15 �Gy h-1 is similar to that for soils of much of the area between Bunbury and Capel in the south-west of Western Australia and is significantly lower than levels for Minninup beach where there are deposits of mineral sands.

scholarly journals Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia

2012 ◽  
Vol 16 (8) ◽  
pp. 2709-2722 ◽  
Author(s):  
W. Dawes ◽  
R. Ali ◽  
S. Varma ◽  
I. Emelyanova ◽  
G. Hodgson ◽  
...  
Keyword(s):  
Land Cover ◽  
Groundwater Recharge ◽  
Western Australia ◽  
Coastal Plain ◽  
Future Climate ◽  
Native Vegetation ◽  
Groundwater Levels ◽  
Swan Coastal Plain ◽  
South West ◽  
Recharge Rates

Abstract. The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south-west Western Australia, provides approximately 60 percent of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15 percent. There is expected to be a reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia. Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A vertical flux manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on climate, land cover type (e.g. native trees, plantation, cropping, urban, wetland), soil type, and taking into account the groundwater depth. In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In areas with land-use change, recharge rates have increased. Where rainfall has declined sufficiently, recharge rates are decreasing, and where compensating factors combine, there is little change to recharge. In the southwestern part of the study area, the patterns of groundwater recharge are dictated primarily by soil, geology and land cover. In the sand-dominated areas, there is little response to future climate change, because groundwater levels are shallow and much rainfall is rejected recharge. Where the combination of native vegetation and clayey surface soils restricts possible infiltration, recharge rates are very sensitive to reductions in rainfall. In the northern part of the study area, both climate and land cover strongly influence recharge rates. Recharge under native vegetation is minimal and is relatively higher where grazing and pasture systems have been introduced after clearing of native vegetation. In some areas, the recharge values can be reduced to almost zero, even under dryland agriculture, if the future climate becomes very dry.

scholarly journals Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia

2012 ◽  
Vol 9 (5) ◽  
pp. 6063-6099 ◽  
Author(s):  
W. Dawes ◽  
R. Ali ◽  
S. Varma ◽  
I. Emelyanova ◽  
G. Hodgson ◽  
...  
Keyword(s):  
Land Cover ◽  
Groundwater Recharge ◽  
Western Australia ◽  
Coastal Plain ◽  
Groundwater Resource ◽  
Annual Rainfall ◽  
Native Vegetation ◽  
Groundwater Levels ◽  
Swan Coastal Plain ◽  
South West

Abstract. The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south west Western Australia, provides approximately 60% of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15%. There is expected to be a continuing reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia. Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A Vertical Flux Manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on land cover type (e.g. native trees, plantation, cropping, urban, wetland), soil type, and taking into account the groundwater depth. These recharge estimates were accumulated on a daily basis for both observed and projected climate scenarios and used in a MODFLOW simulation with monthly stress periods. In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In the Dandaragan Plateau to the north-east of Perth there has been groundwater level rise since the 1970s associated with land clearing, and with rainfall projected to reduce the least in this area the groundwater levels are estimated to continue to rise. Along the coastal zone north of Perth there is an interaction between projected rainfall decline and legislated removal to pine forests. This results in areas of increasing recharge and rising water levels into the future despite a drying climate signal. To the south of Perth city there are large areas where groundwater levels are close to the land surface and not expected to change more than 1m upward or downward over the next two decades; it is beyond the accuracy of the model to conclude any definite trend. In the south western part of the study area, the patterns of groundwater recharge are dictated primarily by soil, geology and land cover. In the sandy Swan (northern boundary) and Scott Coastal Plains (southern boundary) there is little response to future climates, because groundwater levels are shallow and much rainfall is rejected recharge. The profile dries out more in summer but this allows more rainfall to infiltrate in winter. Until winter recharge is insufficient to refill the aquifers these areas will not experience significant falls in groundwater levels. On the Blackwood Plateau however, the combination of native vegetation and clayey surface soils that restrict possible infiltration and recharge mean the area is very sensitive to climate change. With low capacity for recharge and low storage in the aquifers, small reductions in recharge can lead to large reductions in groundwater levels. In the northern part of the study area both climate and land cover strongly influence recharge rates. Recharge under native vegetation is minimal and is relatively higher where grazing and pasture systems have been introduced after clearing of native vegetation. In some areas the low recharge values can be reduced to almost zero, even under dryland agriculture, if the future climate becomes very dry. In the Albany Area the groundwater resource is already over allocated, and the combination of existing permanent native vegetation with decreasing annual rainfall indicate reduced recharge. The area requires a reduction in groundwater abstraction to maintain the sustainability of the existing resource.

Perth Plants

2016 ◽  
Author(s):  
Russell Barrett ◽  
Eng Pin Tay
Keyword(s):  
Western Australia ◽  
Coastal Plain ◽  
Native Plants ◽  
Significant Part ◽  
Additional Species ◽  
Natural Heritage ◽  
City Life ◽  
Swan Coastal Plain ◽  
South West ◽  
The City

The city of Perth is well known and treasured for its areas of protected bushland in the heart of the city. Kings Park and Bold Park represent a significant part of the natural heritage of the Swan Coastal Plain and are an important part of city life. The city is also a gateway to the incredible biodiversity to be found in south-west Western Australia. Perth Plants provides a comprehensive photographic guide to all plants known to occur in the bushlands of Kings Park and Bold Park, both native plants and naturalised weeds. There are 778 species included, representing approximately one-quarter of all the plants in the greater Perth region, and one-tenth of all species known for the south-west of Western Australia. This new edition contains 22 additional species and updated photography throughout. It is an essential reference for anyone interested in the plants of south-west Western Australia, and particularly the Swan Coastal Plain.

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